Additional Concepts
- $$\left\{ \begin{array} { l } x ^ { 2 } + y ^ { 2 } = 145 \\x + y = 17\end{array} \right.$$

question 54

Multiple Choice

Additional Concepts
- $$\left\{ \begin{array} { l } x ^ { 2 } + y ^ { 2 } = 145 \\x + y = 17\end{array} \right.$$

• A) \(\{ ( 9,8 ) , ( 8,9 ) \}\)
• B) \(\{ ( - 9,8 ) , ( - 8,9 ) \}\)
• C) \(\{ ( 9 , - 8 ) , ( 8 , - 9 ) \}\)
• D) \(\{ ( - 9 , - 8 ) , ( - 8 , - 9 ) \}\)

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Definitions:

Marginal Cost

The increase in total production cost when output is increased by one unit.

Variable Cost

Costs that vary directly with the level of production or output, such as materials and labor.

Fixed Cost

Costs that do not vary with the volume of production or sales, such as rent, salaries, and insurance.

Average Cost

The total cost divided by the quantity produced, calculating the cost on a per unit basis.